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US4226169A Expired / Lapsed US ⏱️ 0.0 years remaining

Adjustable expandable cryogenic piston and ring

Assignee: United States Department of Energy
•
Filing: 1978-06-05
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Granted: 1980-10-07
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Expires: 1998-06-05
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Abstract

Abstract The operation of a reciprocating expansion engine for cryogenic refrigeration is improved by changing the pistons and rings so that the piston can be operated from outside the engine to vary the groove in which the piston ring is located. This causes the ring, which is of a flexible material, to be squeezed so that its contact with the wall is subject to external control. This control may be made manually or it may be made automatically in response to instruments that sense the amount of blow-by of the cryogenic fluid and adjust for an optimum blow-by.

Inventors

  • 👤 Peter O. Mazur
  • 👤 Carl B. Pallaver

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 10:55
CPC Classifications
F; F16; F16J; F16J15/00; F16J15/16; F16J15/18; F16J15/184; F16J15/185; F25; F25B; F25B9/00; F25B9/06; F25B2400/00; F25B2400/14; F25B2400/141

Claims Analysis

Total Claims: 3
Claim 1
Independent Claim 211 words
In a reciprocating engine comprising a cylinder (11), a piston (102) reciprocable in said cylinder consisting of an inner portion (104) and an outer portion (106), a sealing ring (112) compressible between the inner portion (104) and the outer portion (106) of the piston (102) against the inner wall of the cylinder (11) and means for adjusting the compression on said sealing ring (112) to vary the pressure of the sealing ring against the wall of the cylinder, the improvement wherein said means for adjusting the compression is operable while the piston is reciprocating and includes a first rod (108) attached to the inner portion (104) and having a threaded upper end, a second rod (110), coaxial with the first rod (108), attached to the outer portion (106), an internally threaded sleeve (124) attached to the second rod (110) which threadedly engages said threaded upper end, an index wheel (126) including a sleeve (128) surrounding threaded sleeve (124) in mating sliding engagement therewith, the mating surface being noncircular in cross section and permitting relative longitudinal movement therebetween and means (142) for rotating index wheel (126) whereby relative longitudinal movement of inner portion (104) and outer portion (106) of piston (102) varies the compression of sealing ring (112) against the cylinder wall.
Claim 2
Dependent Claim 211 words
In a reciprocating engine comprising a cylinder (11), a piston (102) reciprocable in said cylinder consisting of an inner portion (104) and an outer portion (106), a sealing ring (112) compressible between the inner portion (104) and the outer portion (106) of the piston (102) against the inner wall of the cylinder (11) and means for adjusting the compression on said sealing ring (112) to vary the pressure of the sealing ring against the wall of the cylinder, the improvement wherein said means for adjusting the compression is operable while the piston is reciprocating and includes a first rod (108) attached to the inner portion (104) and having a threaded upper end, a second rod (110), coaxial with the first rod (108), attached to the outer portion (106), an internally threaded sleeve (124) attached to the second rod (110) which threadedly engages said threaded upper end, an index wheel (126) including a sleeve (128) surrounding threaded sleeve (124) in mating sliding engagement therewith, the mating surface being noncircular in cross section and permitting relative longitudinal movement therebetween and means (142) for rotating index wheel (126) whereby relative longitudinal movement of inner portion (104) and outer portion (106) of piston (102) varies the compression of sealing ring (112) against the cylinder wall.
Claim 3
Dependent Claim 22 words
The improvement of claim 1 wherein sleeve (128) has a square opening therein and threaded sleeve (124) is octagonal in cross section.

References Cited (Backward Citations)

US125857A Cited
US1468459A Cited
US1495286A Cited
US1558749A Cited
US1740931A Cited
FR711128A Cited
US2496260A Cited
US2365237A Cited
US2847262A Cited
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US4087988A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1983-10-07 1984-04-07 1984-10-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1987-10-07 1988-04-07 1988-10-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1991-10-07 1992-04-07 1992-10-07 $7700.00 Window Closed / Lapsed

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